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Panel / Sub-Panel Question


johnmcda

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House built in 1974 being remodeled which required the service meter to be relocated. The main disconnect is in the panel.

The local AHJ required a new disconnect to be installed at the meter which is 50 feet away from the existing panel.

Does this not make the original panel a sub-panel?

Are the grounds and neutrals now required to be separated?

There are 42 circuits in this 200 amp ITE panel and a sub panel a foot away with 10 circuits. If the grounds and neutrals now have to be separated on the original panel, the repair is going to be miserable and costly.

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Originally posted by johnmcda

House built in 1974 being remodeled which required the service meter to be relocated. The main disconnect is in the panel.

The local AHJ required a new disconnect to be installed at the meter which is 50 feet away from the existing panel.

Does this not make the original panel a sub-panel?

I guess so. The word "sub-panel" doesn't exist in the NEC. It's really a slang term.

Are the grounds and neutrals now required to be separated?

Sure. You aren't allowed to reground the neutral after the service disconnecting means per 250.24(A)(5).

There are 42 circuits in this 200 amp ITE panel and a sub panel a foot away with 10 circuits. If the grounds and neutrals now have to be separated on the original panel, the repair is going to be miserable and costly.

If you don't do it, then every grounded surface that's connected to those two panels will be energized at a level that's equal to the voltage drop in the 50-foot feeder. That could be dangerous. Keep in mind that getting electrocuted can also be miserable and costly.

- Jim Katen, Oregon

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Originally posted by hausdok

Did you check the lable on that ITE panel to see whether it's listed for 42 stabs? That's a lot. Bet some of those need to be moved to that sub-panel.

42 is as big as a residential panel gets, but normally a 200 amp stops at 40 and you have to go 225 to get the extra 2 circuits. If this is an older panel I suppose it could be a 200 amp 42 circuit; not really that much difference.

Brian G.

Lotso Spaces [:-bigeyes

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Originally posted by Brian G

Originally posted by hausdok

Did you check the lable on that ITE panel to see whether it's listed for 42 stabs? That's a lot. Bet some of those need to be moved to that sub-panel.

42 is as big as a residential panel gets, but normally a 200 amp stops at 40 and you have to go 225 to get the extra 2 circuits. If this is an older panel I suppose it could be a 200 amp 42 circuit; not really that much difference.

Brian G.

Lotso Spaces [:-bigeyes

You'll all be interested to know that the 42-circuit limitation will disappear in the 2008 NEC. We might just start to see 54-circuit panels in a few years.

- Jim Katen, Oregon

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Originally posted by Jim Katen

Originally posted by johnmcda

House built in 1974 being remodeled which required the service meter to be relocated. The main disconnect is in the panel.

The local AHJ required a new disconnect to be installed at the meter which is 50 feet away from the existing panel.

Does this not make the original panel a sub-panel?

I guess so. The word "sub-panel" doesn't exist in the NEC. It's really a slang term.

Are the grounds and neutrals now required to be separated?

Sure. You aren't allowed to reground the neutral after the service disconnecting means per 250.24(A)(5).

There are 42 circuits in this 200 amp ITE panel and a sub panel a foot away with 10 circuits. If the grounds and neutrals now have to be separated on the original panel, the repair is going to be miserable and costly.

If you don't do it, then every grounded surface that's connected to those two panels will be energized at a level that's equal to the voltage drop in the 50-foot feeder. That could be dangerous. Keep in mind that getting electrocuted can also be miserable and costly.

- Jim Katen, Oregon

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Originally posted by kurt

I hope so. The circuit restriction is just plain silly.

I'm not so sure. It would be silly if all sparkys knew what they were doing and homeowners never altered thier wiring, but neither is the case. I think the restrictions have probably played a useful part in keeping overloaded panels relatively low in number.

Needless to say, a determined idiot can overload any panel, of any size.

I'm just thinking....has anyone looked at a 42 circuit panel lately? A 54 circuit with all the required air space is gonna be big enough to bury someone in.

Brian G.

Doctor, We Have Another Electrician With a Hernia in the Emergency Room [:-crazy]

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